Patent Number: 6,308,531

Title: Hybrid cycle for the production of liquefied natural gas

Abstract: Refrigeration process for gas liquefaction which utilizes one or more vaporizing refrigerant cycles to provide refrigeration below about C. and a gas expander cycle to provide refrigeration below about C. Each of these two types of refrigerant systems is utilized in an optimum temperature range which maximizes the efficiency of the particular system. A significant fraction of the total refrigeration power required to liquefy the feed gas (typically more than 5% and often more than 10% of the total) can be consumed by the vaporizing refrigerant cycles. The invention can be implemented in the design of a new liquefaction plant or can be utilized as a retrofit or expansion of an existing plant by adding gas expander refrigeration circuit to the existing plant refrigeration system.

Inventors: Roberts; Mark Julian (Kempton, PA), Agrawal; Rakesh (Emmaus, PA)

Assignee: Air Products and Chemicals, Inc.

International Classification: F25J 1/00 (20060101); F25J 1/02 (20060101); F25J 001/00 ()

Expiration Date: 10/30/2018